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This video introduces the method of culturing bacteria, which includes the transfer of one single colony or a tiny amount of broth culture to a new agar plate or a fresh broth using the aseptic…

After performing microbiological experiments, it is important to sterilise the used apparatus and unwanted cultures properly before disposal, so that the environment would not be contaminated by the…

Gram staining is a common method to stain and to differentiate bacteria into two main groups: Gram positive bacteria (when stained purple) and Gram negative bacteria (when stained pink). There are 4…

Micropipettes are used to draw and transfer a small amount of liquid accurately. There are 3 steps in transferring solution using micropipettes, i.e. setting the volume, drawing the liquid and…

進行微生物實驗後，正確消毒及棄置使用過的設備和材料是十分重要的，以確保環境不受微生物污染。本短片介紹兩種常用的消毒方法：浸入濃度為10%的氯漂白劑溶液及高壓滅菌，並介紹如何製備及儲存氯漂白劑溶液，以及高壓滅菌的操作程序及其安全措施。

革蘭氏染色是一種常用來把細菌染色以分類的方法，染色後的細菌可分成兩大類：革蘭氏陽性細菌(被染成紫色的)及革蘭氏陰性細菌(被染成粉紅色的)。革蘭氏染色包括四個步驟，按次序是染色、固定染料顏色、脫色及複染，各步驟需用不同的化學劑和技巧。

微量移液器能準確地抽取並轉移少量液體。使用微量移液器轉移液體涉及三個步驟，包括設定容積、吸取液體和釋放液體。另外，微量移液器可用來混合兩種溶液。 為確保微量移液器能吸取準確的液體份量及不會因操作不當而造成破損，短片會介紹一些使用微量移液器的注意事項。

本節目分成兩個部分。 (一) 中和作用的原理 - 利用石蕊溶液的顏色變化為指標，分別以酸加進鹼和鹼加進酸的實驗來闡明酸和鹼可以互相抵銷。 - 把氫氧化鈉溶液和氫氯酸混合，繼而把混合物放在蒸發皿中加熱，液體完全蒸發後留下白色固體，這固體是氯化鈉（食鹽）。這實驗顯示氫氯酸與氫氧化鈉反應發生中和作用，產生氯化鈉（食鹽）和水。 -…

1. Ask for and give advice on simple matters such as skateboarding on busy streets 2. Justify one’s behaviour and point of view in simple situations in discussions and find a solution 3. Seek…

本節目分成三個部分。 (一)…

This programme is divisible into 3 parts as follows: 1. Solutes, Solvents, Solutions The concepts of solutes, solvents, solutions and dissolving are clarified with reference to everyday examples. An…